/Engine/Source/Runtime/SlateCore/Public/Layout/BasicLayoutWidgetSlot.h
typedef [SlateAttributePrivate::TSlateMemberAttributeRef](API\Runtime\SlateCore\Types\Attributes\TSlateMemberAttributeRef)< [SlotPaddingAttributeType](API\Runtime\SlateCore\Layout\TPaddingSingleWidgetSlotMixin\SlotPaddingAttri-) > SlotPaddingAttributeRefType